uselocale(3) Library Functions Manual uselocale(3)
NAME
uselocale - set/get the locale for the calling thread
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <locale.h>
locale_t uselocale(locale_t newloc);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
uselocale():
Since glibc 2.10:
_XOPEN_SOURCE >= 700
Before glibc 2.10:
_GNU_SOURCE
DESCRIPTION
The uselocale() function sets the current locale for the calling thread,
and returns the thread's previously current locale. After a successful
call to uselocale(), any calls by this thread to functions that depend
on the locale will operate as though the locale has been set to newloc.
The newloc argument can have one of the following values:
A handle returned by a call to newlocale(3) or duplocale(3)
The calling thread's current locale is set to the specified lo-
cale.
The special locale object handle LC_GLOBAL_LOCALE
The calling thread's current locale is set to the global locale
determined by setlocale(3).
(locale_t) 0
The calling thread's current locale is left unchanged (and the
current locale is returned as the function result).
RETURN VALUE
On success, uselocale() returns the locale handle that was set by the
previous call to uselocale() in this thread, or LC_GLOBAL_LOCALE if
there was no such previous call. On error, it returns (locale_t) 0, and
sets errno to indicate the error.
ERRORS
EINVAL newloc does not refer to a valid locale object.
STANDARDS
POSIX.1-2008.
HISTORY
glibc 2.3. POSIX.1-2008.
NOTES
Unlike setlocale(3), uselocale() does not allow selective replacement of
individual locale categories. To employ a locale that differs in only a
few categories from the current locale, use calls to duplocale(3) and
newlocale(3) to obtain a locale object equivalent to the current locale
and modify the desired categories in that object.
EXAMPLES
See newlocale(3) and duplocale(3).
SEE ALSO
locale(1), duplocale(3), freelocale(3), newlocale(3), setlocale(3), lo-
cale(5), locale(7)
Linux man-pages 6.9.1 2024-05-02 uselocale(3)
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